Remotely actuated multi-use modular explosive ordnance disposal rocket dearmer

ABSTRACT

A novel dearmer enables EOD technicians to propel dearmer projectiles using conventional electric .50 caliber blank cartridges or conventional non-electric 12 gauge blank cartridges. The dearmer projectiles may render energetic threats safe without requiring an opposing force to offset the recoil. The conventional blank cartridge functions as a rocket motor that supplies gas to a converging/diverging nozzle. Alternatively, liquid is loaded into the dearmer (creating a liquid rocket effect) and the EOD projectile is propelled toward a target from the end of the dearmer opposite the liquid.

STATEMENT OF GOVERNMENT INTEREST

The invention described herein may be manufactured and used by or forthe Government of the United States of America for Governmental purposeswithout the payment of any royalties thereon or therefor.

FIELD OF THE INVENTION

The invention relates in general to explosive ordnance disposal (EOD)and in particular to apparatus for propelling dearmer projectiles torender various energetic threats safe.

BACKGROUND OF THE INVENTION

Some conventional technology used to render energetic threats (forexample, fuzes coupled to warheads, etc.) safe rely on using highpressure cartridges to build up pressure inside of a barrel. The highpressure in the barrel propels a projectile/slug out of the barrel andcauses the projectile/slug to impact the threat location. An apparatusthat uses this conventional technology is, for example, the MK 2Dearmer. The MK 2 Dearmer uses interior ballistics to propel theprojectile forward. The forward velocity of the projectile is partly dueto the entire large mass of the barrel that offsets the recoil as theprojectile travels down the barrel. However, EOD technicians requirelightweight equipment to enable manual transportation of the equipmenton long distance missions. To propel a projectile fast enough, highpressure is required. In conventional technology, such as the MK 2Dearmer, for example, the barrel size and large mass is dictated by thehigh internal pressure.

A need exists for a lightweight apparatus to propel EOD projectiles andrender energetic threats safe.

SUMMARY OF THE INVENTION

One aspect of the invention is a dearmer including a blank cartridgeconfigured to create propulsion gas. An air-tight insert is disposedaround the blank cartridge and conforms to an exterior profile of theblank cartridge. An EOD projectile is disposed adjacent a base of theblank cartridge. An outer sleeve is disposed around the air-tightinsert. A converging/diverging nozzle is disposed adjacent to an end ofthe blank cartridge, which is opposite the base of the blank cartridgeand is fixed to the outer sleeve. The converging/diverging nozzle isconfigured to receive the propulsion gas and thereby propel the dearmertoward a target.

In one exemplary embodiment, the EOD projectile is attached to the outersleeve. In another exemplary embodiment, the EOD projectile is integralwith the outer sleeve.

The dearmer may include a rupture disk disposed between the end of theblank cartridge opposite the base of the blank cartridge and theconverging/diverging nozzle.

The dearmer may be disposed in a launch tube prior to ignition of theblank cartridge.

In another aspect of the invention, the converging/diverging nozzle isomitted and a volume of liquid is disposed adjacent an end of the blankcartridge opposite the base of the blank cartridge and is contained inthe air-tight insert such that the propulsion gas impacts the volume ofliquid and propels the dearmer toward a target.

The invention will be better understood, and further objects, features,and advantages thereof will become more apparent from the followingdescription of the exemplary embodiments, taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily to scale, like orcorresponding parts are denoted by like or corresponding referencenumerals.

FIG. 1 is a cutaway side view, partially in section, of one exemplaryembodiment of a dearmer.

FIG. 2 is a cutaway side view, partially in section, of a secondexemplary embodiment of a dearmer.

FIG. 3 is a cutaway side view, partially in section, of a thirdexemplary embodiment of a dearmer.

FIG. 4 is a side sectional view of a launch tube.

FIG. 5 is a schematic drawing of a target energetic threat.

DETAILED DESCRIPTION OF THE INVENTION

A novel dearmer enables EOD technicians to propel various dearmerprojectiles using conventional electric .50 caliber blank cartridges orconventional non-electric 12 gauge blank cartridges. The dearmerprojectiles may render energetic threats safe without requiring anopposing force to offset the recoil. In one exemplary embodiment, theconventional blank cartridge functions as a rocket motor that suppliesgas to a converging/diverging nozzle. In another exemplary embodiment,liquid is loaded into the dearmer (creating a liquid rocket effect) andthe EOD projectile is propelled toward a target from the end of thedearmer that is opposite the liquid.

FIG. 1 is a cutaway side view, partially in section, of one exemplaryembodiment of a dearmer 10. Dearmer 10 includes a blank cartridge 12,for example, a conventional electric .50 caliber blank cartridge or aconventional non-electric 12 gauge blank cartridge. In the case of anelectric blank cartridge, the cartridge is remotely initiated via leadwires 14 that lead from the base 18 of cartridge 12 to a remotelocation. In the case of a non-electric blank cartridge, the cartridgeis remotely initiated via a shock tube (not shown) that extends from thebase of the blank cartridge to a remote location. Blank cartridge 12 issurrounded by an air-tight insert 16 that conforms to the exteriorprofile of blank cartridge 12. Insert 16 may be made of light weightmaterial, for example, aluminum, plastic or wood.

An EOD projectile 28 is disposed adjacent base 18 of the blank cartridge12. EOD projectile 28 may be made of, for example, steel, tungsten,metal alloys, and composites. Projectile 28 may be, for example, aconventional dearmer projectile. Conventional dearmer projectilesinclude a standard slug, a flat head slug, a chisel head slug, a wedgeslug and a forked slug, for example. Key parameters of an EOD sluginclude velocity, diameter, material of construction, length, mass, etc.These parameters are important to produce the needed exterior andterminal ballistics.

An outer sleeve 20 is disposed around the insert 16. Outer sleeve 20 maybe made of, for example, steel, carbon fiber or titanium. The thicknessof outer sleeve 20 may be, for example, in a range of about 0.125 inchesto about 0.375 inches. Outer sleeve 20 may be designed for a single useor multiple uses. For single use, the wall thickness of outer sleeve 20may be less than for multiple uses because the sleeve 20 need notsurvive repeated pressure loadings. For single use designs, the sleeve20 may be allowed to permanently deform thereby enabling use of athinner wall thickness compared to multiple use designs where permanentdeformation is not desired. For multiple use configurations, lightweightmaterials and/or composites may be used, such as carbon fiber, titanium,etc. In the instant invention, it is desirable to minimize the weight ofthe entire assembly because the rocket actuation will be moving theentire mass (blank cartridge 12, insert 16, outer sleeve 20, nozzle 24and EOD projectile 28) forward toward the target. By contrast, inconventional dearmer technology, it is generally not desirable tominimize the magnitude of the recoiling mass (barrel) because the barrelis freely flying backwards and a lower recoiling mass can diminish theforward velocity of the projectile.

A converging/diverging nozzle 24 may be disposed adjacent an end of theblank cartridge 12 opposite the base 18 of the blank cartridge and fixedto outer sleeve 20. Nozzle 24 may be fixed to outer sleeve 20 with athreaded connection 22, for example. In the exemplary embodiment of FIG.1, outer sleeve 20 also partly surrounds projectile 28. Projectile 28may be fixed to sleeve 20 with threads (not shown) or O-rings 21, forexample. A rupture disk 26 may be disposed between the end of the blankcartridge 12 opposite the base 18 of the blank cartridge and theconverging/diverging nozzle 24.

FIG. 2 is a cutaway side view, partially in section, of a secondexemplary embodiment of a dearmer 30. Dearmer 30 is similar to dearmer10 except that the EOD projectile 32 is formed integrally with the outersleeve 34.

FIG. 3 is a cutaway side view, partially in section, of a thirdexemplary embodiment of a dearmer 40. Dearmer 40 is similar to dearmer30 except the converging/diverging nozzle 24 is replaced with a columnof liquid 42 in the interior of insert 16. Liquid 42 may be, forexample, water. Insert 16 may be fixed to outer sleeve 20 with athreaded connection 44, for example. A seal 46, such as a plastic capseal, may be used to contain liquid 42 in insert 16 until blankcartridge 12 is ignited. The propellant gas created by blank cartridge12 impacts liquid 42 in insert 16 to create a liquid rocket.

FIG. 4 is a side sectional view of a launch tube 50. Tube 50 may be athin-walled tube made of, for example, plastic or carbon fiber. Dearmer10 or 30 or 40 may be placed in launch tube 50 prior to ignition of theblank cartridge 12. Alternatively, dearmer 10 or 30 or 40 may be placedon a rail (not shown) prior to igniting the blank cartridge 12. Thedearmer is ejected from the thin-walled tube 50 or runs along the railuntil the propellant in the blank cartridge 12 is expended. Thus, theEOD projectile 28 or 32 and the entire dearmer assembly are projectedtoward the desired target 52 (FIG. 5) in a direction opposite thedirection of the propulsion gases that are exhausted from the blankcartridge 12. In FIGS. 1-3, the projectile 28 or 32 and the dearmerassembly are projected in the direction shown by arrow A.

The overall assembly is very much lighter than conventional dearmersbecause a high-strength pressure vessel is not required in the noveldearmer to contain and direct high-pressure propellant gas. In addition,there is no rearward recoil with the novel dearmer. In a conventionalgun barrel, gas pressure builds up and pushes against a heavy, solidprojectile until it exits the barrel. In the novel dearmer, gas pressurebuilds up but does not push against a heavy projectile. Rather, the gasis moved at high velocity through a nozzle (or against a column ofliquid) to create force. A conventional gun barrel uses gas pressure tomove a heavy solid mass at a lower velocity. The novel dearmer uses alightweight gas mass that moves at a much higher velocity through anozzle (or against a column of liquid).

Any numerical parameters set forth in the specification and attachedclaims are approximations that may vary depending upon the desiredproperties sought to be obtained by the present invention. At the veryleast, and not as an attempt to limit the application of the doctrine ofequivalents to the scope of the claims, each numerical parameter shouldat least be construed in light of the number of significant digits andby applying ordinary rounding.

What is claimed is:
 1. A dearmer, comprising: a blank cartridge beingconfigured to create propulsion gas; an air-tight insert being disposedaround the blank cartridge and conforming to an exterior profile of theblank cartridge; an EOD projectile being disposed adjacent a base of theblank cartridge; an outer sleeve being disposed around the air-tightinsert; and a converging-diverging nozzle being disposed adjacent an endof the blank cartridge that is opposite the base of the blank cartridgeand fixed to the outer sleeve, wherein the converging-diverging nozzleis configured to receive the propulsion gas and thereby propel thedearmer toward a target to dearm the target.
 2. The dearmer of claim 1,wherein the EOD projectile is attached to the outer sleeve.
 3. Thedearmer of claim 1, wherein the EOD projectile is integral with theouter sleeve.
 4. The dearmer of claim 1, wherein the blank cartridge isone of an electric .50 caliber blank cartridge and a non-electric 12gauge blank cartridge.
 5. The dearmer of claim 1, wherein the EODprojectile is a conventional EOD slug.
 6. The dearmer of claim 1,further comprising a rupture disk being disposed between the end of theblank cartridge opposite the base of the blank cartridge and theconverging-diverging nozzle.
 7. The dearmer of claim 1, furthercomprising a launch tube, wherein the dearmer is disposed in the launchtube prior to ignition of the blank cartridge.
 8. A method of dearmingan energetic threat, comprising: providing the dearmer of claim 1;igniting the blank cartridge; moving the propulsion gas through theconverging-diverging nozzle; and propelling the dearmer toward thetarget.
 9. The method of claim 8, further comprising, before ignitingthe blank cartridge, placing the dearmer in a tube.
 10. The method ofclaim 8, wherein said igniting the blank cartridge includes igniting oneof an electric .50 caliber blank cartridge and a non-electric 12 gaugeblank cartridge.